Block-signal system.



No. 882,553. PATENTED MAR. 24, 1908 F. B. COREY BLOCK SIGNAL SYSTEM.

APPLICATION FILED MAB. 9. 1905.

w/bneasess 1 H //)I/6/72'70/1 E -Ma 5 5y Freud 5. Care UN TED STATES PATENT OFFICE.

FRED B. COREY, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

BLOCK-SIGNAL SYSTEM.

Specification of Letters 'Patent' Patented March 24, 1908.

Application filed March 9, 1905. Serial No. 249,178.

To all whom it may concern:

Be it known that I, FRED B. COREY, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Block-Signal Systems, of

which the following is a specification.

My invention relates to block signal systems, and is particularly applicable, though not necessarily limited, to alternatingcurrent systems. In many cases-it is desirable to employ alternating current for operating such systems. Thus, for instance, in the case of an electric railway on which direct current .is used for the driving motors, it is important that the leakage of power current from the rails should not affect the operation of the signals. This end may be obtained by employing relays responsive only to alternating current and supplying alternating current-for the signal system.

My invention is particularly applicable to i such a system, and its object is to provide a Y so . coil of the relay of the block in the rear connected to the same transformer. 1

My invention will best be understood by reference to the accompanying drawing which shows diagrammatically an alternating-current block signal system arranged in accordance with my invention.

In the drawing R represents one of the track rails which is shown continuous so as to serve-as a return conductor for the power current. The other rail is sectionalized in the usual manner, portions-of five sections R to-R being shown. Home and distant Sig; nalslare shown at or near the entrance to eac block, H and D representing respectively the home and distant signals at the entrance to .the block R The reference letters applied to the apparatus iatthe entrance to each block are dis tinguished by the numeral corresponding to the number of'the block, .as indicated by the reference letter applied to the sectional rail;

In addition to the home and distant signals, the apparatus at the entrance to each block consists of operating mechanism for each signal, a source of current for the 0 erating mechanism and a controlling re ay. Thus, I have indicated at the entrance to block R a magnet winding h as an o crating mechanism for the home signal The connections between the magnet winding h and the si nal II are not shown, it being understood t at any well known type of operating mechanism may be employed, and that the magnet winding 71/ is urely diagrammatic, representing any well known form of signal driving mechanism. Similarly, the magnet winding (1 represents the operating or driving means for the distant signal D. B represents a source of current for the op erating coils h and d, and 1" re resents an alternating-current relay cont-r0 ing the circuits of the operating mechanisms.

I have shown a relayof the type which comprises two relatively movable coils, one connected to the track circuit and the other supplied with alternating current of the same frequency indeendently of the track circuits. When .a ternating current is flowing through both-relay coils, a torque is .pro duced between the .two coils in one direction or the other, according .to the relative direction of current-flow through the two coils; which torque may be utilized to close the circuits of the operating mechanism for one or both signals. When the relay coil connected to the track circuit is short-circuited by a car or train on the block the relay has no torque, and the circuits of bothoperating mechanisms are thereby opened, permitting the signals to go to danger by gravity. direct current through one of the relay coils can have no effect, since the other coil produces an alternating flux, so that the signal system .is unafiected by the leakage of power current from the rails. L re resents a linewire extending along the trac and su plied with alternating current at a potentia suitable for economic transmission. Transformers T T 'etc., are provided at the entranceto each block. The primary of each transformer is supplied from the line-wire L, one terminal being connected to the line-wire and the other to the continuous rail R. The secondary ot'each transformer supplies both a track circuit and a coil of a relay of the block in the rear. Thus, for instance,it will be seen that the movable coil a of relay 1' is the signals of H and D at clear position. It connected across the track circuit of the will be observed that the reversing switches, block R while the stationary coil f is 0011- while operating to reverse the relative connected to the secondary of the transformer nections of transformer and track circuit, do T at the entrance of the block in advance. not disturb the connections from the trans- 70 f The secondary of this transformer T is also former to the relay coil supplied therefrom. f connected through the reversing switch S, It will be understood that the transformers which is operatively connected to the operatare arranged as has been heretofore suging mechanism for the home signal H, to the gested 'in similar systems, with poor regulafarther end of the block R that is, the section, so that the short-circuit on the secondary of the transformer T supplies the ondary does not produce an excessive flow 1 track circuit R and also supplies one coil of of primary current nor lower the potential 1 the relay 1* controlling the signals at the on the line-wire L. i entrance of block R Although I have shown my invention ap- 3 5 The operation is then as follows: With a plied to a system employing both home and car or train in the block R, as indicated at C, distant signals, it will be understood that the relay coil a is short-circuited and the my invention is not limited to this particucontact arm carried thereby assumes the lar arrangement. The system exactly as position shown, and is held there either by illustrated is applicable to systems em 10ygravity or by a spring. With the contact ing only home si nals, the only change eing arm in the osition shown, the circuits of the omission of t e distant signals, the drivboth operating mechanisms 71, and d are ing mechanism for the distant signals and opened and the signals H and D are held the reversing switches. For the sake of in danger position by their counter-weights, simplicity I have shown my invention diashowing the presence of a car in the block R. grammatically, and it will be understood The car C in the block R short-circuits a that it is applicable to a system employing art of the secondary winding of the transany suitable well known type of apparatus. ormer T, and this short-circuit acts as a Accordingly, I do not desire to limit myself short-circuit on the entire secondary of the to the particular construction and arrange- 0 transformer. Conse uently the coil f 2 of the ment of parts here shown, but aim in the aprelay T which is su p ied from this secondary pended claims to cover all vmodifications is denergized anc the coil a is allowed to which are within the scope of my invention. assume the position shown, opening the cir- What I claim as new, and desire to secure cuits of the operating mechanisms h and by Letters Patent of the United States, is,- (Z and allowing the signals H and D to go 1. In a block signal system, separate to danger. The conditions at the entrance sources for supplying current to the track to block R are thus repeated at the encircuits of the several blocks, relays each trance to blockR Thus the block It serves comprising two coils, one connected to the as an overlap for the block R which is frerails of a block and the other connected to 40 quently desirable where the blocks are short, the same source of current that supplies the .and this result is obtained without the emtrack circuit of an adjacent block, and sigployment of any additionalapparatus. The nals controlled by said relays. signal H being'in dangerposition, the re- 2. In a block signal system, separate versing switch S which is operatively consources for supplying current to the track nected thereto is in the position shown. circuits of the several blocks, relays each With the switch in this position the relative comprising two relatively-movable coils, one direction of current supplied to the block R connected to the rails of a block and the from the secondary of the tranformer T is other connected to the same source of oursuch that the torque produced in the relay rent that supplies the track circuit of the r is in a direction to move the contact arm block in advance, and signals controlled by toward the right, as shown. In this posisaid relays. tion the circuit of the operating mechanism 3. In a block signal system, a source of 71, is closed, while that of d is opened. The alternating current extending along the home signal H is consequently clear, while roadway, transformers energized therefrom the distant signal D is at danger giving a and each having its secondary connected to caution indication in the usual manner. the track circuit of a block, relays each com- Since the home signal H is in clear position, prising two coils, one connected to the track the reversing switch S is in such a position circuit of a block and the other connected to that the relative direction of the current supthe secondary of the same transformer that 1 plied to block 4 through the switch S from supplies the track circuit of the block in ad- 1 the secondary of transformer T is such that vance, and signals controlled by said relays. i the direction of torque in the relay 1" pro- 4. In a block signal system, a source of duces a movement of the contact arm toward alternating current extending along the the left, so as to close the circuits of both roadway, transformers energized therefrom operating mechanisms h and d, which hold and each having its secondary connected to 13 the track circuit of a block, relays each com prising two relatively-movable coils, one connected to the track circuit of a block and the other connected to the secondary of the same transformer that supplies the track circuit of the block in advance, and signals controlled by said relays.

5. In a block signal system, home and distant signals for each block, means for supplying current to the track circuits of the several blocks, relays each comprising two coils, one connected to the rails of a block and the other connected to the same source of current that supplies the track circuit of the block in advance, and a reversing switch op eratively connected to each home signal and arranged when operated to reverse the relative direction of current flow through the preceding block without reversing the relative direction of flow through the relay coil supplied from the same source.

6. In a block signal system, home and distant signals, a source of alternating current extending along the roadway, transformers energized from said source and each having its secondary connected to the track circuit of a block, relays each comprising two coils, one connected to the rails of a block and the other connected to the secondary of the same transformer that supplies the circuit of the block in advance, and a reversing switch operatively connected to each home signal and arranged to reverse the relative connections of the track circuit of the preceding block and the transformer supplying said circuit without disturbing the connections from said transformer to the relay coil supplied therefrom.

7. In a block signal system, home and distant signals, a source of alternating current extending along the roadway, transformers energized from said source and each having its secondary connected to the track circuit of a block, relays each comprising two relatively movable coils, one connected to the rails of a block and the other connected to the secondary of the same transformer that supplies the track circuit of the block in ad- Vance, and a reversing switch operatively connected to each home signal and arranged. to reverse the relative connections of the track circuit of the preceding block and the transformer supplying said circuit without disturbing the connections from said transformer to the relay coil supplied therefrom.

8. In a block signal system, home and distant signals, a source of alternating current extending along the roadway, transformers energized from said source and each having its secondary connected to the track circuit of a block, relays each comprising two relatively-movable coils, one connected to the rails of a block and the other connected to the secondary of the same transformer that supplies the track circuit of the block in advance, a reversing switch operatively connected to each home signal and arranged to reverse the relative connections of the track circuit of the block in the rear, and the transformer supplying said circuit without disturbing the connections from said transformer to the relay coil supplied therefrom, and a contact arm carried by the movable coil of each relay controlling both a home and a distant signal. 1

9. In a block signal system, separate sources for supplying current to the track circuits of the several blocks, relays each comprising two cooperating coils, one connected to the rails of a block and the other connected to the same source of current that supplies the track circuit of the block in advance, and signals controlled by said relays.

10. In a block signal system, signals for each block arranged to indicate danger, caution and clear, means for supplying current to the track circuits of the several blocks, relays each comprising two cooperating coils, one connected to the rails of a block and the other connected to the same source of current that supplies the track circuit of the block in advance, and a reversing switch operatively connected to the signal mechanism for each block arranged when operated to reverse the relative direction of current-flow through the preceding block without reversing the relative direction of flow through the relay coil supplied from the same source.

11. In a block signal system, a transformer having a secondary winding connected in circuit with the rails of a block and supplying volta e thereto, and a device controlling a signa for the preceding'block connected i in another circuit with said transformer, whereby the signal-controlling device is affected inductively through said transformer when said rails are short-circuited by a train. v

12. In a block signal system, in combina tion with the rails of a block, a transformer for supplyin voltage to said block, a device controlling a signal for the preceding block,

and connections from different terminals of said transformer both to the rails of said block and to the signal-controlling device, whereby the signal-controlling device is affected inductively through said transformer by a train short-circuiting the rails of said block.

13. In a block signal system, the combination with track circuit sections and signals for such sections, and a source of energy connected at one end of each of said sections, a relay connected to the other end of each of said sections comprising a field energized from the source of energy energizing the next adjacent section, and an armature connected across the rails of the section in which it is included. and capable of three functional positions, means for controlling the functional positions of said armature, and means for making said signals give indications corresponding to the said three positions of said armature.

14. In a block signal system, the combination with insulated track circuit sections and signals for such sections, of means located at one end of each of said sections for creating a difference of potential between the rails thereof, a relay connected at the other end of each of said sections comprising a member energized by a potential proportional to the difference of potential between the rails of the next adjacent section, and a rotating member energized by the .difierence of potential'between the rails of the section in which it is included and capable of three functional positions, means for controlling said functional positions, means for operating one of said signals to the proceed position by one of said functional positions of said armature, means for operating two of said signals to the proceed position by another functional position of said armature, and means for operating both of said si nals to the stop position by the third unctional position of said armature.

,In witness whereof I have hereunto set my hand this seventh day of March, 1905.

FRED B. COREY.

Witnesses:

-BENJAMIN B. HULL,

HELEN ORFORD. 

